The Major West Coast Windstorm of December 12, 1995 a perspective by Wolf Read

Every so many years, there arrives a windstorm that seems like a contender for challenging the great Columbus Day storm of 1962 for "largest wind event on record." Such blows include, but are not limited to March 26-27, 1971, November 14, 1981, and January 20, 1993. Though there has often been a lot of dramatic press coverage about such storms--with some good reason, as they were fairly powerful, even life-threatening, events--none of these windstorms have matched the grandeur of Columbus Day 1962. None. December 11-12, 1995, saw the development of yet another contender for top storm, a low that "bombed" (a slang term for explosive cyclogenesis, which is when a low pressure center deepens rapidly) off of the California coast, then tracked northeast-ward up the west coast into Washington, blasting towns and cities all the way up the U.S. West Coast. This storm almost matched the Columbus Day storm peak gust for peak gust along the immediate coast, and even exceeded it in select regions, like in the San Francisco Bay Area. But further north, the December 1995 storm didn't reach the strength of the Columbus Day blow in the Willamette Valley and in the Puget Lowlands. For Oregon, the lower wind velocities were partly due to the fact that the December 1995 storm generally did not track as closely to the coast as did the 1962 "Big Blow." The Columbus Day Storm hugged Oregon's Coast at a distance of 50-75 miles, starting from the southern border all the way up, heading in a generally northward track. The December 1995 storm started much further offshore of SW Oregon and raced northeastward, as an excerpt from this report issued at 9:45 PM PST Monday December 11, 1995 suggests: "Satellite imagery and ocean buoy reports confirm the development of an intense low pressure center 600 miles off the coast of Oregon. Forecast models continue to show the low moving northeast along the coast and into northwest Washington by Tuesday evening." Another report at 12:15 PM PST Tuesday December 12, 1995 reads: "At 12 Noon the intense storm was located about 100 miles west of Astoria Oregon and was moving northeastward towards the extreme northwest tip of Washington. By 4 PM PST it should be near Tatoosh Island." The greater distance offshore appears have been the big factor that prevented the kind of terrific gale seen in 1962 from striking Oregon. This can't be the reason why much of Western Washington was spared a Columbus-Day-like gale. After the 1995 cyclone passed the latitude of Astoria, it finally did come within a distance equal to the 1962 storm. A report from the NWS Seattle issued at 2 PM PST Tuesday December 12, 1995 mentions: "At 2 PM...The intense storm was located about 50 miles northwest of Astoria Oregon and moving northeast. The storm center is now expected to move across the Olympic Peninsula by 5 PM." The low did cross the Olympic Peninsula, putting the 1995 center much closer to many Western Washington locations when compared to the 1962 center. Stronger winds can expected nearer the center, where the steepest gradients often reside. Yet these locations didn't suffer winds any higher than places in Oregon. It appears that the December 1995 low was a bit broader than the Columbus Day Storm, with gradients not quite as dramatic. One indicator of this is with the Astoria-Hoquiam (AST-HOQ) measure of pressure gradient. The December 12, 1995 windstorm produced a peak AST-HOQ gradient of +8.6 mb (+0.25") at 19:00 as the low moved ashore just north of Hoquiam. The Columbus Day Storm produced a peak AST-HOQ gradient of +10.8 mb (+0.32") at 21:00 as the low scooted by just offshore. Due to the difference in tracks, the December 1995 storm was favored for a maximal gradient when compared to the Columbus Day Storm. That the Columbus Day Storm managed 2.2 mb higher than the 1995 event with less favorable low-center orientation suggest a more tightly wound cyclone in 1962. One other factor probably contributed to lower wind speeds throughout Western Oregon and Washington on December 12, 1995: storm speed. The Columbus Day Storm moved more rapidly than the 1995 event, and this difference could have contributed to the higher wind speeds witnessed in the earlier storm. Figure 1, below, was found on a San Francisco State University website on this storm: Explosively Developing Cyclone. This image was taken at 04:00 PST, just as the winds were beginning to escalate in the San Francisco Bay Area. The exact center of the low is northeast of the tip of the bent-back occlusion. The core was rather elongated to the northeast, and was showing some signs of developing a secondary center right off of Northwest Oregon.

From the few datapoints available, it seems that most of the big 955 to 975 mb cyclones that follow northward tracks close to the U. S. West Coast ("Inside 130", as NWS forecasters like to say, which referrs to east of 130º W longitude) tend to produce maximum wind gusts of about 60 to 95 mph at offical stations on the coast and 50 to 75 mph at official stations inland. This is the standard scenario. This is generally what happened during the large events in October 1950, March 1971, November 1981, and during the December 1995 storm examined on this web page. Peak wind velocity among these storms, and other lesser events, varies with a rough correlation to minimum central pressure. The Columbus Day Storm was different. It's minimum central pressure of about 960 mb wasn't that unusual among the big cyclones. December 1995 was deeper. However, the Columbus Day winds were unusual. Gusts reached about 80 to 140 mph at official stations on the Oregon coast, and 85 to 125 mph at stations inland. This makes the Columbus Day Storm an outlier. It is off-the-curve unique. A singularity. An event like the Columbus Day Storm probably won't happen again for another 100 years, maybe even 1,000. The Columbus Day Storm probably should be treated as its own category--especially when trying to forecast the peak wind potential of a new cyclogenic bomb based on windstorm climatology. Figure 1, below, depicts the track that the December 12, 1995 cyclone followed. The 1995 low continued to deepen as it moved northward, somewhat unlike the Columbus Day Storm, which reached peak intensity off the Oregon Coast, and then slowly degraded as it raced northward.

Personal Experience What follows is what I recorded in my journal during the December 1995 windstorm, with some notes on damage seen some time after the event. Keep in mind that, at the time, I lived in El Cerrito, a small incorporation on the east shore of the San Francisco Bay. This put me in the center of a region that saw windspeeds that challenged the Columbus Day Storm:

December 12, 1995: Tuesday 08:45 HRS: (El Cerrito, CA) BIG storm this morning. After months of dry--very little rain since June 20! five-and-one-half months of sun and fog--a couple of major storms have finally broken through the monotony. The first--yesterday--dumped a lot of rain on us: 3.5"+ in SFO, up to 7.0" in some regions. Following this rain, a strong low has moved toward the coast north of us. Our pressure is 29.62" and steady now (the low has stalled). This storm center has been swinging in solid bands of moisture, as well as kicking in winds of 50-75 mph at the surface throughout the Bay Area. Our power is out, along with 300,000 homes in the PG&E district. Trees are down all over. One fell on a minivan, crushing it. Two blocked an onramp to the Golden Gate Bridge near Presidio. One park, I'm guessing the Presidio, reported 72 trees down. Roofs are flying off as well. A carport shed its top and dropped it across 4 southbound lanes and 2 northbound lanes of 101 [south SF peninsula]. I also heard a report of a condo losing its roof, and a restaurant in SFO. Flooding is prominent as well: HWY-17 has lanes flooded, 280 in Daly City, other roads as well (Highway 4 yesterday). The Bay Bridges were closed earlier, and are now open to car traffic--no trucks or campers. This is a major storm. Another is coming in. It may not be as windy, but is expected to dump more heavy rain on top of ground saturated already, so the weather service is saying the next storm is extremely dangerous. Latest report: Still 300,000 homes without power, unofficial report of 90 mph gusts near Eureka. I'd say we've been gusting to 60 mph locally--some of the gusts were loud hitting the building and shook the place enough to feel like an earthquake. I had the flashlight standing on its broad light-end fall over in one gust (4-cell Maglite). Needless to say, I'm staying home from work (though I may go in later, but I doubt it).~0910 HRS. 20:30 HRS: Our power finally got restored at 20:00! Thirteen hours w/o power! The absurdity is that houses only block away had power. Home on the small rise to the west glowed, as well as on Albany Hill. Homes to the north by one block also had power. I haven't seen any news yet, so haven't been able to catch up on the damage from the morning's gale. I will note that a radio tower blew over on San Bruno mountain, knocking out the station that I was listening to at the time (07:03~). Many roofs flew from various locals, and San Francisco's high rises shook and swayed so much that in one instance a Christmas tree on the top floor fell over. The storm ripped all the way up the West Coast, hitting west Oregon hard, Washington with a vengeance: Shelton: 80 mph, Auburn 70 mph, Seattle 60 mph, Everett 46 mph, Alkai Pt. 52 mph so far with gusts to 100 mph on Washington's coast. I got this from my Dad, whom I just talked to on the phone. The storm had just started up there, so it looks like they'll be in for a fun night. A note: our peak winds were in the 70-75 mph range with locally higher gusts, though I think our highest winds here in El Cerrito were 55-60 mph (70+ at SFO airport). Areas of highest damage include Redwood City and Pleasant Hill. This is all I can say, 'cuz I'm still trying to get the TV/VCR to work so I can see the news. And my hand is tired (been drawing all day). ~2050 HRS. December 13, 1995: Wednesday 20:57 HRS: (El Cerrito, CA) I've read a bunch of official stuff on the storm of yesterday. Peak gust of 85 mph at SFSU, 75 mph at Alameda Naval Base in Oakland, 70 mph at SFO [upgraded to 74 mph, I believe]. These are just a few: 103 mph at Angel Island was another noteworthy peak (wow!!!). Two people died in the Bay Area from trees falling on their houses, one from a tree smashing their car. Two 230,000 volt transmission towers were toppled in the South Bay (PG&E owned, of course). The San Francisco conservatory was severely damaged structurally, and plants inside suffered greatly, all to the tune of $10,000,000 dollars. The SF Zoo's aviary also suffered losses. Other noteworthy weather events include 2.66" of rain in 45 minutes at the Alameda Naval Station. Up to 15.01" of rain fell at Russian River Sunday night to Tuesday, 5.33" at SFO, 5-9" in many North Bay locations Oakland up and over 12" at Saulsalito. We certainly made up for the lack of rain in October and November. Sacramento lost many trees and had powerlines down all over, yet fortunately had no fatalities. We were slapped hard, but some of the most amazing stuff happened in Western Washington. The low trekked across the Olympic Peninsula from my understanding, and pressures dropped to 958 Mb at Ellis (-I'll have to check this) Island!! [This reading was for the Cape Elizabeth buoy, actually.] What's more amazing is that SeaTac Airport dropped to 970 Mb (28.65") as the low passed! Read: 28.65--I'm shocked. That's about what Astoria dropped to in the great Columbus Day storm of 1962, and it happened far inland nontheless. I'd've never guessed that SEA would achieve so near a record established on the coast! What a storm. However, winds at SEA weren't so impressive, gusting to only 47 mph by the data I have. Other places reached higher, upwards of 59 in Olympia, 52 in Bellingham, 60 at Bremorton, 80 (as mentioned) in Shelton, 78 in North Bend, WA, North Bend, OR, hit 107 mph! (But not achieving the 138 mph recorded in the Columbus Day storm [confused with Newport!]) many coastal locales in Oregon hit between 90 and 110 (even 112) mph. [Portland peaked at 62 mph.] Spokane, WA, did not escape, hitting a damaging 74 mph. WA did not get the heavy rain of CA, though, in this storm. January 28, 1996: Sunday Today, Silven and I hiked up the meadow, and through the surrounding woods with the Zuidema's two golden retrievers Rascal and Charlie, who usually go on these walks with me. I was scouring the forest [in Scotts Valley, CA] for wind damage from the December 12 windstorm. Their [the Zuidema's] power had been knocked out for 4 days from that storm, so I had expected to see much damage in the forest which I had hiked so much. No such thing. I could hardly find felled branches, let alone fallen trees. My hiking grounds appeared to have been spared any major damage. Until I reached the saw mill. One of the huge redwoods that was a member of the small grove which surrounded the saw mill had its tip broken many years ago. As a result, it for two growth tips and continued its extension into the sky. One tip, the one on the south side, was smaller than the north tip. The north tip grew to a vast size, one that would have made a healthy-sized tree in its own right. During the great windstorm of 1995, the north tip, shearing down a plane of weakness undoubtedly as old as the tip itself, snapped clean off. Dropping its massive 50' + length over easily 75-100' of space, the tip smashed the lumber, or saw, mill into a pile of broken plastic roof and 2x4s, all buried under the shattered branches of the redwood trunk and all the other trees the failed tip brought with it on its plummet earthward. The mill was gone, smashed out of existence, buried by a single blow. This, the only tree to break in the area for quite some distance around. Near an orchard being reclaimed by the local wildlife, such as lizards and snakes, and trees of every description. A single redwood, breaking, burying the saw mill with its cascade of wood and green needles. Another victory for a little understood world. 2020 HRS. February 19, 1996: Monday (Holiday!) 18:21 HRS (Home, Martinez, CA) Ha! Sitting by a fire (Duraflame) after a strong storm blew through, dumping heavy rain and producing 20 to 40 mph wind gusts. At least two more storms are expected in the next few days, fronts swinging under a strong semipermanent low offshore to the NW. The next one, due Tues night is expected to be very strong, and also the coldest storm of the season so far. We've already had the lowest barometer thusfar at 29.52" of so (lowest for winter), with the last low at 29.60" in the Dec 12, 1995 windstorm. Speaking of that storm, Silven and I drove out to the Bay Area Discovery Museum today, in the driving--at one time blinding on Highway 101 north--rain and gusty wind. A number of large trees had been blown down by the Dec 12 storm there in a forest alongside a hill on the west part of the [BADM] grounds, and in the US Coast Guard area. One spot, right at the base of the steep hill near the road, had a swath of, say, 20-25 trees blown over--a near total flattening, and a rare sight, though I only saw the stumps, for the boles had been sawed away, and it looked like a few trees in the swath hadn't been uprooted, but there was no way, of course, to see if they had been topped by the gale. Near the swath, which left the remaining stand of cypress looking very toothpickish and bare with just green leaves and branches at their top (light competition), a eucalyptus had also fallen and damaged the roof and wall of a USCG warehouse-like building. Quite a sight. I'd say the wind probably gusted in the 85-90 mph range there, maybe enhanced by the hill's aerodynamics-->it is notable that only that small area had near total treefall while many exposed trees did not fall or suffer major damage.

General Storm Data Minimum Pressures and Peak Gradients Table 1, below, lists the lowest barometric pressure readings at various locations in the December 12, 1995 windstorm, and the Columbus Day Storm and compares them, when available. The readings for the December 1995 storm are spectacularly low. Note that Salem in 1995 dropped as low as did Tatoosh Island in 1962! The Columbus Day low-pressure center was beginning to fill significantly as it headed into the waters off of Washington. The lowest central pressure for the storm of 1962 was about 28.30" at 11:00 AM, when the low was 205 miles west of Eureka, CA (this information comes from Franklin, Dorothy, "West Coast Disaster," 1962). It seems that the December 1995 low didn't undergo much filling before making landfall on the Olympic Peninsula. Maybe the difference in tracks allowed the 1995 low to maintain integrity as it raced inland. After all, the Columbus Day Storm spent a large part of its existence close to shore, and the degrading effects of the vertical topography of the west. The December 1995 low, on its northeast track, didn't get very close to land until it had reached the latitude of Washington. There's a nice trend of increasing difference in barometric minimums in a northward direction, from about 0.10" in Northern California to about 0.30" in Northern Washington, with some exceptions (like Toledo). This reflects on the December 1995 storm's northeast tendency compared to the Columbus Day Storm's northward migration. Washington stations, in general were much closer to the center of action in 1995. The Columbus Day Storm's weakening offshore of Washington also contributed. Source for data in table: National Climatic Data Center, unedited surface observation forms, unless otherwise noted.

Location Lowest Pressure 1995 Lowest Pressure 1962 Difference California:       Arcata 29.05" 29.13" -0.08" Oregon:       Astoria 28.53" 28.62" -0.09" North Bend 28.72" 28.70" +0.02" Eugene 28.77" 28.86" -0.09" Salem 28.73" 28.86" -0.13" Portland 28.71" 28.84" -0.13" The Dalles   29.13"   Washington:       Hoquiam 28.53" 28.66" -0.13" Cape Elizabeth [1] 28.31"     Destruction I. [2] 28.38" 28.54" -0.16" Tatoosh Island [3] 28.49" 28.72" -0.23" Toledo 28.65" 28.70" -0.05" Olympia 28.61" 28.83" -0.22" Sea-Tac [3] 28.65" 28.90" -0.25" Navy Whidby 28.64" 28.90" -0.26" Bellingham 28.63" 28.91" -0.28"

Table 1, notes. [1] The 1995 value (958.8 mb) is from Buoy 46041 Cape Elizabeth, 52 miles west of Aberdeen, WA. From the National Data Buoy Center historical meteorological data. [2] The 1995 figure is from the Destruction Island C-MAN station, and was obtained from the National Data Buoy Center historical meteorological data. The 1962 figure is from Decker, Fred W., Cramer, Owen P., Harper, Byron P, "The Columbus Day 'Big Blow' in Oregon," Weatherwise, December 1962. [3] The 1995 figure is from the Tatoosh Island C-MAN station, and was obtained from the National Data Buoy Center historical meteorological data. [3] Sadly, the unedited surface observation forms for some stations during the December 12, 1995 windstorm are lost due to a corrupt data file at the NCDC. This includes Quillayute, Seattle, Medford and San Francisco. The minimum reading from Seattle is from the NCDC Storm Data publication for December 1995.

Table 2, below, lists the lowest barometric pressures achieved during the December 12, 1995 storm for the 11 key Pacific Northwest locations used in general comparison between storms on this website, and the time of occurrence of the barometric minimums. Many of these values are all-time record low pressures, including the readings at Arcata, Bellingham, Eugene, Olympia, Salem and Seattle. The minimum of 28.53" (966.1 mb) at Astoria, often noted as the all-time low pressure for that location, was short of the 28.45" (963.4 mb) reading witnessed durng the Storm King of Janaury 9, 1880. Portland's reading of 28.73" (973.0 mb) is at least third place, being short of the 28.72" (972.6 mb) reading from the great December 4, 1951 windstorm and the 28.56" (967.2 mb) reading from the January 9, 1880 event. At North Bend, the low pressure of 28.70" (971.9 mb) during the Columbus Day Storm was slightly lower than the 28.72" (972.6 mb) during the 1995 gale. At Tatoosh Island, the barometric pressure was at or below 28.75" (973.5 mb) from the 06:00 observation to 20:00, an incredible 14 hours! At Seattle, pressures held at or below 28.75" from 12:00 to 19:00, or seven hours. The long period of low pressure, plus the close association in time of pressure minimums at Western Washington locations, mark a very deep, broad low, one that appears to have been elongated in an west-to-east manner. The average minimum pressure of 28.69" (971.6 mb) for these stations is significantly lower than the 28.85" (977.0 mb) 11-station average for the Columbus Day Storm, and the 28.90" (978.7 mb) average for the December 4, 1951 cyclone. The December 12, 1995 cyclone produced the lowest pressure minimum average out of any cyclone to strike the Pacific Northwest in the 1950-to-present era. Source: Pressure data is from the National Climatic Data Center, Unedited Surface Observation Forms (most stations), and the National Data Buoy Center historical meteorological data (Tatoosh Island C-MAN station TTIW used in place of Quillayute, and West Point C-MAN station WPOW1 used in place of Sea-Tac).

Location Lowest Pressure Approx Time of Lowest Pressure California:     Arcata 29.05" 06:00 HRS, 12th Oregon:     North Bend 28.72" 08:00 HRS, 12th Astoria 28.53" 13:00 HRS, 12th Medford [1] MM MM Eugene 28.77" 09:00 HRS, 12th Salem 28.73" 12:00 HRS, 12th Portland 28.73" 13:00 HRS, 12th Washington:     Quillayute [2] 28.49" 15:00 HRS, 12th Olympia 28.61" 15:00 HRS, 12th Seattle [3] 28.63" 14:00 HRS, 12th Bellingham 28.63" 15:00 HRS, 12th       AVERAGE [4] 28.69"

Table 2, notes. [1] Medford's unedited surface observation forms lost due to a corrupt data file at the NCDC. [2] Quillayute's unedited surface observation forms lost due to a corrupt data file at the NCDC. Tatoosh Island C-MAN station TTIW used in place of Quillayute. [3] Sea-Tac's unedited surface observation forms lost due to a corrupt data file at the NCDC. West Point C-MAN station WPOW use in place of Sea-Tac. [4] Due to missing data from Medford (see [1] above), the average in the case of the December 12, 1995 storm is from the ten available samples.

Table 3, below, is a list of the maximum hourly pressure gradients, and time of occurrence, for the December 12, 1995 windstorm. Some of these measures are spectacular. The ACV-AST value of +33.0 mb (+0.97") ties the peak value for the Columbus Day Storm. The OTH-UIL reading of +31.8 mb (+0.94") beats the peak value of +27.3 mb (+0.81") witnessed during the Columbus Day Storm by a decisive margin. The Columbus Day Storm was clearly weakening as it moved into Washington's offshore waters, and this may account for the lower OTH-UIL (TTI) gradient for the 1962 event. The peak PDX-SEA gradient of +15.3 mb (+0.45") is second only to the +15.4 mb (+0.455") value generated by the Inauguration Day storm of 1993, and is significantly above the +9.9 mb (+0.29") peak value for the Columbus Day Storm--though it should be kept in mind that the PDX-SEA reading in December 1995 is actually a PDX-WPOW (West Point) reading, which is over a longer distance and therefore probably a millibar or two high when compared to the standard PDX-SEA measure. Source: Pressure data is from the National Climatic Data Center, Unedited Surface Observation Forms (most stations), and the National Data Buoy Center historical meteorological data (Tatoosh Island C-MAN station TTIW used in place of Quillayute, and West Point C-MAN station WPOW1 used in place of Sea-Tac).

Location Max Gradient, mb Approx Time of Max Gradient Coast:     ACV-OTH 16.6 10:00 HRS, 12th OTH-AST 22.6 16:00 HRS, 12th AST-UIL [1] 18.3 20:00 HRS, 12th ACV-AST 33.0 15:00 HRS, 12th OTH-UIL [1] 31.8 18:00 HRS, 12th Interior:     MFR-EUG [2] MM MM EUG-PDX 9.1 16:00 HRS, 12th PDX-SEA [3] 15.3 19:00 HRS, 12th SEA-BLI [3] 8.7 21:00 HRS, 12th AST-DLS [4] -14.1 06:00 HRS, 12th

Table 3, notes. [1] Quillayute's unedited surface observation forms lost due to a corrupt data file at the NCDC. Tatoosh Island C-MAN station TTIW used in place of Quillayute. Incidentially, this makes for more accurate comparisons between this storm and those before the 1964 opening year for the Quillayute station, which replaced the Tatoosh station for many decades. [2] Medford's unedited surface observation forms lost due to a corrupt data file at the NCDC. [3] Sea-Tac's unedited surface observation forms lost due to a corrupt data file at the NCDC. West Point C-MAN station WPOW use in place of Sea-Tac. The different positions of SEA and WPOW probably cause the PDX-WPOW gradient to be about 1-2 mb high and the WPOW-BLI 1-2 mb low when compared to the standard PDX-SEA and SEA-BLI measures. [4] Sea-level pressure unrecorded at The Dalles from 23:00 to 05:00 each day. The peak gradient listed, having occurred right at the first DLS observation of the 12th, could have been higher before 06:00.

Pressure Tendencies Table 4, below, lists the maximum hourly pressure falls and rises achieved during the December 12, 1995 storm for 11 Pacific Northwest stations. The peak -5.1 mb (-0.15") hourly drop at North Bend is the highest on record, slightly beating out the -5.0 mb (-0.148") recorded as the great Columbus Day Storm raced northward toward the station. The rest of the values, both in fall and rise, are quite strong, but other storms in history have exceeded these tendencies--in some cases by a large margin. In terms of the 11-station averages, the Columbus Day Storm was clearly ahead of the December 12, 1995 event on both counts with a -4.6 mb (-0.14") average hourly declension, and a +6.2 mb (+0.18") average hourly climb. The -3.5 mb (-0.10") average for the December 12, 1995 storm is behind at least five storms in the 1950-to-present era: November 14, 1981 (-3.7 mb / -0.11"), October 12, 1962, December 16, 1961 (-3.6 mb / -0.105"), December 21, 1955 (-4.1 mb / -0.12") and December 4, 1951 (-4.4 mb / -0.13"). And the +4.5 mb (+0.13") average for the 1995 storm is behind at least three storms in the 1950-to-present era: October 12, 1962, December 20, 1961 (+4.6 mb / +0.136") and February 24, 1958 (+5.2 mb / +0.15" based on eight stations). Some of the more spectacular pressure surges during the December 12, 1995 windstorm happened at buoys and automated stations along the Washington shoreline as the bent-back occlusion pushed inland behind the low center. At Destruction Island, starting at 20:00 on December 12th, the pressure surged from 972.3 mb (28.71") to 979.3 mb (28.92") in a single hour--that's +7.0 mb (+0.21"). At the time of the pressure jump, strong west-southwest winds poured in, sustaining at 62 mph and gusting to 70. Buoy 46041 Cape Elizabeth witnessed a +6.0 mb (+0.18") surge during the same hour, with southwest winds escalating to 43 mph gusting to 58. Welcome to the Information Age, era of twitchy machines. The ever-familiar corrupt data files from the NCDC for the MFR, SEA and UIL stations turns up here, with missing and or substituted values. Source: Pressure data is from the National Climatic Data Center, Unedited Surface Observation Forms (most stations), and the National Data Buoy Center historical meteorological data (Tatoosh Island C-MAN station TTIW used in place of Quillayute, and West Point C-MAN station WPOW1 used in place of Sea-Tac) and for the Destruction Island and Cape Elizabeth descriptions.

Maximum Pressure Tendencies for the December 12, 1995 Storm Location Max Hrly Fall mb Time of Max Fall PST Max Hrly Rise mb Time of Max Rise PST California:         Arcata -3.7 19:00 HRS, 11th +4.8 09:00 HRS, 12th Oregon:         North Bend -5.1 22:00 HRS, 11th +3.3 16:00 HRS, 12th Astoria -3.7 01:00 HRS, 12th +5.7 18:00 HRS, 12th Medford [1] MM MM MM MM Eugene -3.8 23:00 HRS, 11th +3.7 16:00 HRS, 12th Salem -3.2 02:00 HRS, 12th +4.0 17:00 HRS, 12th Portland -3.2 00:00 HRS, 12th +3.7 17:00 HRS, 12th Washington:         Quillayute [2] -3.3 04:00 HRS, 12th +5.2 22:00 HRS, 12th Olympia [3] -2.8 01:00 HRS, 12th +5.4 20:00 HRS, 12th Seattle [4] -3.2 06:00 HRS, 12th +4.3 21:00 HRS, 12th Bellingham -3.2 04:00 HRS, 12th +4.8 23:00 HRS, 12th           AVERAGE [5] -3.5   +4.5

Table 3, notes. [1] Medford's unedited surface observation forms lost due to a corrupt data file at the NCDC. [2] Quillayute's unedited surface observation forms lost due to a corrupt data file at the NCDC. Tatoosh Island C-MAN station TTIW used in place of Quillayute. Incidentially, this makes for more accurate comparisons between this storm and those before the 1964 opening year for the Quillayute station, which replaced the Tatoosh station for many decades. [3] The -2.8 mb/hr drop is the first of two occurrences, the other being at 02:00 on the 12th. [4] Sea-Tac's unedited surface observation forms lost due to a corrupt data file at the NCDC. West Point C-MAN station WPOW use in place of Sea-Tac. [5] Due to missing data from Medford (see [1] above), the average in the case of the December 12, 1995 storm is from the ten available samples.

Peak Wind and Gust Table 5, below, provides a list of peak gusts from the December 1995 windstorm, and the Columbus Day Storm of 1962, so that the two storms can be compared. I also offer the difference in the peak gust speeds, and what that means in terms of wind force (i.e. the difference in the strength of the wind, as opposed the velocity). Wind force increases with the square of the velocity. In other words, when the velocity is doubled, the force is quadrupled. A 50 mph wind at sea level produces about 10 lbs per square foot of force. A 100 mph gust hits with four times the force--about 40 lbs per square foot, not 20 as one might suppose by simply doubling the force in correspondance with the increase in velocity. By examining the peak gusts in this light, we see that the Columbus Day Storm had significantly more punch than the December 1995 windstorm in many areas. Sources include the National Climatic Data Center (such as the Local Climatological Data, Unedited Surface Observation Forms, and online Climate Visualization Database), the National Weather Service at Portland (such as the online monthly summaries for Eugene, Salem and Portland) and Seattle (For example, Bellingham's peak gust was mentioned in a High Wind Warning Statement issued at 12:12 AM PST Wednesday December 13, 1995), and Franklin, Dorothy, "West Coast Disaster," 1962. Some of the figures below are tentative, and could be changed as I find more information on these two storms. Interestingly, for North Bend, OR, neither of these storms were the strongest in the past 40 years--November 1981 saw a gust to 92 mph at this location!

Location Dec 1995 Peak (mph) Oct 1962 Peak (mph) Difference (mph) Force Difference (number of times difference in strength of peak gust, with year of strongest storm listed). California:         San Francisco 74 63 [3] +11 1.38 X (1995) Erueka/Arcata 64 58 +6 1.21 X (1995) Redding/Red Bluff 85 81 +4 1.10 X (1995) Crescent City 59 69 -10 1.37X (1962) Oregon:         Coast:         North Bend 86 81 +5 1.13 X (1995) Newport 107 138 -31 1.66 X (1962) Astoria 62 96 -34 2.40 X (1962) Willamette Valley:         Eugene 49 86 -37 3.08 X (1962) Salem 59 90 -31 2.33 X (1962) Portland 62 / 74 [1] 104 [1] -30 1.98 X (1962) Washington:   Coast:         Hoquiam 69 81 -12 1.38X (1962) Quillayute 43 N/A     Tatoosh Island 61 78 -17 1.63X (1962) Interior:         Toledo 67 89 -22 1.76X (1962) Olympia 66 78 -12 1.40 X (1962) Sea-Tac Airport 60 58 [3] +2 1.07 X (1995) Bremorton 60 75 -15 1.56 X (1962) Everett 64 81 [2] -17 1.60 X (1962) Bellingham 76 98 -22 1.66 X (1962)

Table 5, notes. [1] 62 mph is from the ASOS system. Apparently peak gust recorders registered 74 mph (source, National Weather Service, Portland, "Climate of Portland." This is also the source for the peak gust of 104 mph cited for the Columbus Day Storm.) [2] From NCDC's ClimVis Database. [3] The Seattle Naval Air Station (decomissioned in 1970) recorded a peak gust of 66 mph in the Columbus Day Storm, according to the NCDC's ClimVis Database.

Table 5 provided a straightforward comparison, however, study of the units-of-measure, and sensor location information, show that the data from the two storms were not collected in the same manner, rendering comparisons dubious. Table 6, below, shows winds at some of the above stations, and the associated instrument information, such as sensor height and location. Differences between 1962 and 1995 are significant.

Peak Winds, October 12, 1962 and Instrument Data Location Peak Wind Measure Peak Gust Measure Sensor Hgt Sensor Location SFO 50 1-Min 63 Instant 20 feet Field EUG 63 1-Min 86 Instant 20 feet Field SLE 58 1-Min 90 Instant 20 feet Field PDX 88 Fast Mi 104 Estimated 33 feet Field AST 44 1-Min 96 Instant 46 feet Field OLM 58 1-Min 78 Instant 20 feet Field SEA 44 1-Min 58 Instant 20 feet Field TTI 66 Fast Mi 78 Instant 64 feet   Peak Winds, December 12, 1995 and Instrument Data Location Peak Wind Measure Peak Gust Measure Sensor Hgt Sensor Location in Relation To 1962 Readings SFO 54 2-Min 74 Instant 33 feet Moved 2400 feet SE, Field EUG 40 2-Min 49 5-Sec ASOS Moved, Field SLE 46 2-Min 59 5-Sec ASOS Field PDX 51 2-Min 62 5-Sec ASOS Moved, Elevation Raised 200', Field AST 46 2-Min 62 5-Sec ASOS Field OLM 45 2-Min 57 5-Sec ASOS Field SEA 37 2-Min 60 Instant 20 feet Moved 2800 feet SW, Field TTI 51 2-Min 61 5-sec 83 feet C-MAN Station (DACT)

With the exception of some stations in Washington, wind speeds for the December 1995 storm were measured on the new ASOS/AWOS system, which provides wind data in a 2-minute average format with 5-second peak gust. The ASOS User's Guide states specifically that, "In ASOS, the peak wind is determined from the highest 5-second average wind speed that exceeds 25 knots since the last generated METAR." At the time of the Columbus Day Storm, the Weather Bureau recorded either average 1-minute winds and/or fastest mile, with peak instantaneous gust. For example, in the October 1962 Local Climatological Data for the Eugene airport, the peak wind is listed under fastest 1-minute, and it is noted that, "a momentary gust of 86 MPH [was] observed." Further complicating matters, however, is the old method of computing average wind, which, as noted in the discussion of wind speeds for November 14, 1981, has the possibility of observer error. Observer error may explain some of the wide variation between peak 1-minute wind and peak instantaneous gust recorded at some sites in the Columbus Day Storm. Note the 44 mph gusting to 58 at Sea-Tac and the 44 mph gusting to 96 at Astoria. It is possible that Astoria's actual peak 1-minute wind was higher than 44 mph--though the Columbus Day Storm was noted for extremely gusty winds, as corroborated by a 26 mph gusting to 81 reading at North Bend. It's probably telling that, on the standard Surface Observation Form used at the time of the Columbus Day Storm, the wording is such: "Fastest observed 1-minute wind speed ______ m. p. h. [Emphasis added]" This is one area where ASOS shines: wind measure is controlled by computer, which makes the methodology between stations consistent. If ASOS and AWOS stations provided a 1-minute average and instantaneous peak gust, these readings would tend to be higher than the new standard 2-minute average and 5-second peak. This means that the reported speeds for the 1995 storm are probably low when compared to the figures for the Columbus Day Storm. In an example from my own records, the February 7, 2002 South Valley windstorm produced a peak instantaneous gust of 27 mph on a new, well-calibrated anemometer. I videotaped the event, and later captured the footage on computer so that wind velocity in 0.5-second increments could be recorded. The data are shown in Figure 3, below. From this data, a running 5-second average was calculated. At 21 mph, the 5-second peak was much lower than the instant gust. That's a difference of 23%! Figure 3 clearly shows the "smoothing" effect that a 5-second running mean has on peak instant gusts. The average difference between the instant reading and the 5-second reading was 1.68 mph for this four-minute stretch of wind. With an average velocity of 11.38 mph over the four minutes, the average difference was 15%. Running averages for 30, 60 and 120 seconds were also calculated. Wind speed lowered for each time interval, though the difference is less between the longer time-periods. The peak one and two minute averages were quite close: 14.0 mph and 13.3, or within 5%.

The peak instantaneous gust reported on December 12, 1995 for Portland, 74 mph, was taken on the old pre-ASOS wind gauge, and is therefore an instant (though now unoffical) reading [personal communication with Dave Willson, Lead Forecaster for NWS Portland, 2002]. With a peak 5-second gust of 62 mph at the Portland ASOS, there's a difference of 17% between the two readings, which is close to that 23% figure noted above. Averaging the two percentages and taking off with this "peak gust adjustment," the 5-second peak at Eugene converts to an instantaneous gust of 59 mph. Salem changes to 71 mph, and Astoria to 75. These are still significantly lower than the storm of '62, but not as much as the new National Weather Service wind measure format might suggest. A difference of 5% doesn't change the 2-minute averages much, keeping some of the 1962 readings significantly on top. Due to its high velocity, Portland's fastest mile of 88 mph in 1962 can be read as a 41-second average (essentially, wind moving at 88 mph will cover a mile in 41 seconds). In the wind data I took for the 2002 storm, the difference between the 41-second and 2-minute averages is about 15%. Portland's peak 2-minute wind of 51 mph for the December 1995 storm converts to a 59 mph 41-second speed, still far off the 1962 mark--that's a difference in wind force of about 2.2 times. There are many objections to these adjustments, not the least of which is that the anemometer used for the conversions is of a different make than an ASOS wind sensor. With a difference of about 40% between peak 5-second and peak 2-minute, it is clear that the winds at my location were significantly more turbulent than at less obstructed airport-based anemometers, which usually vary between 15% and 25% between average speed and gust. And the sample resolution of 0.5 second is also probably different. The above paragraph mainly serves to show what potential differences might exist between the two formats. The average difference between peak gust and peak 5-second wind at ASOS stations is probably more like 5-10% by conservative estimate. Unfortunately, changes in wind record format aren't the only complications introduced when comparing wind speeds between the two storms. Modern ASOS wind sensors tend to be higher than the 20-foot standard of the pre-automated era. According to the ASOS User's Guide, Most ASOS anemometers are put at the new FAA standard of 10 meters, or 32.8 feet, with some at 27 feet, depending on "site-specific restrictions or requirements." Anyone who's played around with setting up an anemometer knows that a relatively small increase in height can have a significant affect on peak winds. A change of 7-13 feet is 25-40% higher than the old 20-foot standard. Wind speeds will tend to be higher with the new system. This, in effect, means that the adjusted peak gusts are probably high in comparison to the Columbus Day Storm, with a few exceptions, like Astoria, where the anemometer has been lowered to meet the new standard. Ultimately, what is left after this analysis is a fairly muddy comparison that suggests the Columbus Day Storm had more powerful winds, at least at most Oregon locations. There is some evidence in the data that suggest the 1995 event was somewhat of a flip-flop of the 1962 one, with the strongest impact happening in Northern California, then again in the Seattle Area. The peak 5-second wind of 74 mph at San Francisco shines far above the 62 mph instantaneous gust in 1962, and Sea-Tac's pathetic 58 mph for the Columbus Day Storm is a mark below the 60 recorded in 1995. Despite well-calibrated anemometers set up at many locations, it seems that, like for the January 1880 cyclone, anecdotal evidence is still king when comparing windstorms! Comparison of the newspaper accounts, and personal experiences, suggest rather unanimously that, even though December 1995 was bad, the level of emergency that resulted during the 1962 Big Blow was far, far worse. Table 7, below, shows the December 12, 1995 windstorm's peak wind and gust for the stations in Table 6, adjusted to reflect the differences in sensor height and wind measure. Note that the power law formula was intended for sustained winds, not wind gusts, so its application in the peak gust column is a bit dubious.

December 1995 Peak Winds Adjusted to October 1962 Standards Modification Factors: 1.05 for 2-min to 1-min wind, 1.10 for 5-sec to instant gust. Standard power law formula applied to sensor height differences. Location Peak Wind Measure Peak Gust Measure Adjust Hgt SFO 53 1-Min 69 Instant 20 feet EUG 39 1-Min 50 Instant 20 feet SLE 45 1-Min 60 Instant 20 feet PDX 54 1-Min 68 Instant 33 feet AST 51 1-Min 72 Instant 46 feet OLM 44 1-Min 58 Instant 20 feet SEA 39 1-Min 60 Instant 20 feet TTI 52 1-Min 65 Instant 64 feet

These adjusted December 12, 1995 peak wind values can then be compared to the Columbus Day Storm, as is done in Table 8, below. A positive value in the difference column reflects stronger winds during the 1962 event, negative reflects stronger winds during the 1995 event. The results put the Columbus Day Storm clearly on top for many places in Oregon. December 1995 has the edge over the 1962 storm far south in San Francisco, and in the Seattle area--but the difference is minor compared to the Columbus Day Storm's huge margin in places like the Willamette Valley. The Columbus Day Storm's lead narrows northward, indicative of the 1962 cyclone's weakening off the Washington Coast more than a significantly larger 1995 impact for Washington.

Adjusted Peak Winds for December 1995 Compared to Peak Winds for October 1962 Location Peak Wind Oct 1962 mph Peak Wind Dec 1995 mph Difference mph Peak Gust Oct 1962 Peak Gust Dec 1995 Difference mph SFO 50 53 -3 63 69 -6 EUG 63 39 24 86 50 36 SLE 58 45 13 90 60 30 PDX 63 54 9 104 68 36 AST 44 51 -7 96 72 24 OLM 58 44 14 78 58 20 SEA 44 39 5 58 60 -2 TTI 49 52 -3 78 65 13

With the differences in wind measure now noted, the discussion can now move to Table 9, below, a list of the peak wind and gust for eleven key stations in the Pacific Northwest, their direction, and their time of occurrence. By my own personal methodology, a wind event rates the term "windstorm" when the average peak gust of these eleven stations reaches 39.0 mph (gale force) or higher. This ranking favors those storms that follow a northward path close to the U.S. Pacific Coast, and for good reason--such storms affect the largest land area, and therefore are potentially the most destructive. The incredibly deep December 12, 1995 cyclone followed such a path, with damaging, sometimes outright destructive, winds striking many points along the way, and this windstorm's average peak gust, 61.4 mph, ranks this event among the few great storms of history. Taken without modification for difference in wind measure, the 1995 strom is behind just three storms from the 1950-to-present era: January 15, 1951 with an average of 61.6 mph, October 12, 1962 with an average of 80.5, and November 14, 1981 with an average of 65.9. With a conservative 10% adjustment upward for peak gusts at known ASOS stations, the December 1995 storm shows an average peak of 64.4, which places it 3rd behind the November 14, 1981 and Columbus Day Storms. That's a close 3rd, and it could very well have edged second with an unusually high peak instant gust at a station or two.

Location	Peak Wind mph	Direction Pk Wnd degrees	Obs Time of Peak Wind PST	Peak Gust mph	Direction Pk Gst degrees	Obs Time of Peak Gust PST
California:
Arcata	35	220º	07:53 HRS, 12th	58	220º	07:42 HRS, 12th
Oregon:
North Bend [1]	69	180º	11:49 HRS, 12th	86	180º	11:49 HRS, 12th
Astoria	46	200º	17:57 HRS, 12th	62	190º	17:56 HRS, 12th
Medford [2]	31	150º	MM	45	140º	MM
Eugene	40	180º	13:02 HRS, 12th	49	180º	13:01 HRS, 12th
Salem	46	170º	13:23 HRS, 12th	59	180º	13:23 HRS, 12th
Portland	51	170º	13:17 HRS, 12th	62	170º	14:20 HRS, 12th
Washington:
Quillayute [3]	51	237º	22:00 HRS, 12th	61	237º	22:00 HRS, 12th
Olympia	45	160º	14:41 HRS, 12th	57	140º	14:48 HRS, 12th
Sea-Tac [4]	37	180º	19:00 HRS, 12th	60	180º	MM
Bellingham	37	190º	23:58 HRS, 12th	76	200º	22:34 HRS, 12th
AVERAGE [5]	44.4	185º		61.4	183º

Table 9, notes. [1] Due to equipment failure during the storm, possibly due to power failure, wind direction at North Bend was estimated at the time of peak winds. Its probable that the peak velocities were also estimates, but this isn't clear on the surface observation form. [2] Medford's unedited surface observation forms lost due to a corrupt data file at the NCDC. Wind data are from the Local Climatological Data monthly summary for December 1995. Time of peak wind and gust not noted in the publication. [3] Quillayute's unedited surface observation forms lost due to a corrupt data file at the NCDC. Quillayute's peak gust not noted on the December 1995 Local Climatological Data montly summary. Tatoosh Island C-MAN station TTIW used in place of Quillayute. Incidentially, this makes for more accurate comparisons between this storm and those before the 1964 opening year for the Quillayute station, which replaced the Tatoosh station for many decades. And it also probably gives a boost to the 11-station averages, for winds at Tatoosh tend to be higher than at Quillayute. [4] Sea-Tac's unedited surface observation forms lost due to a corrupt data file at the NCDC. Peak wind is from the 3-hourly observations noted in the Local Climatological Data monthly summary for Sea-Tac, December 1995, as is peak gust. [5] Assumes 5-second and instant gusts are the same.

Table 10, below, lists the peak gusts reported by NWS Seattle spotters (with a few from Oregon) during the December 12,1995 windstorm. These reports were posted during the storm by NWS Seattle, and I carefully collected them all as they became available. Taken at face value, some of these peaks approached Columbus Day Storm levels, and in the storm reports it is mentioned that 60 to 80 mph readings were also seen in the Willamette Valley of Oregon. However, it is interesting that the higher winds managed to miss many official stations in Dec 1995--though the difference in wind measure, 5-second peak next to peak instant gust, may account for some of the disparity. With few exceptions during the Columbus Day Storm, the official stations were slammed just as hard as the unofficial ones (indeed, a number of official sites had instrument failure due to power outages and/or structural damage!). The Sea-Tac Airport is the one big exception. Despite a 100 mph reading at the nearby Renton Airport, Sea-Tac only managed a peak of 58 mph in 1962 (note that the anemometer at Renton was at 64' above ground level, fully 44' above SeaTac's 20'). Sea-Tac's reading is so much lower than the typical 75-95 mph gusts in the region that it is unusual. It should be noted that some of the locations below are more wind prone than official sites. I've seen Auburn yield high readings in windstorms previous to December 1995, such as 70 mph during the January 16, 1986 storm, so a high reading at this location my not be that unusual for a storm of this type. Enumclaw typically gets strong east winds ahead of deep, NE-trending storms. Portland, OR, sees a similar effect as winds rush down the Columbia River Gorge.

Location	Peak Wind	Time
Enumclaw, WA	60 mph (E)	6:00 AM
Wickersham, WA	50 mph	8:00 AM
Alsea, OR (Near Corvallis)	70 mph	11:30 AM
Sea Lion Caves, OR	118 mph	12:00 PM
Chinook, WA	78 mph	1:30 PM
Puyallup, WA (Pierce 6)	65 mph (SE)	2:00 PM
Grayland Beach, WA (Grasy Harbor 2)	50 mph	2:20 PM
Ocean Shores, WA (Grays Harbor 5)	54 mph	2:30 PM
Seattle, WA (King 23)	40 mph	2:45 PM
Ocean Shores, WA (Grays Harbor 5)	54 mph	5:00 PM
Mukilteo, WA (Snohomish 30)	58 mph	6:00 PM
Tacoma, WA (Pierce 20)	56 mph	6:20 PM
Seattle, WA (King 23)	51 mph	6:20 PM
Marysville, WA	46 mph	6:20 PM
Auburn, WA	70 mph	6:30 PM
Olympia, WA (Thurston 1)	65 mph	6:30 PM
Long Beach, WA	61 mph	6:50 PM
Harbor Island, Seattle, WA	78 mph	7:40 PM
Aberdeen, WA (Grays Harbor 10H)	55 mph	7:47 PM
Lummi Island, WA	50 mph	7:50 PM
Edmonds, WA	64 mph	8:20 PM
Mukilteo, WA (Snohomish 30)	86 mph	8:20 PM
North Bend, WA	78 mph	8:20 PM
Bellingham, WA (Whatcom 8)	54 mph (S)	8:40 PM
Marysville, WA (Snohomish 35)	55 mph (SE)	8:40 PM

Table 11, below, lists some storm reports posted by the NWS at Monterey during the December 12, 1995 windstorm. Some of the rainfall readings are truly spectacular. For comparison to the Columbus Day Storm: San Francisco reported a 3-day rain total of 4.78" by 3 PM Saturday, October 13, 1962, which brought the season total (starting July 1st) to 5.09", which was the second highest in 113 years of record (1904 saw 7.12" by Oct 13th). The Oakland International Airport was soaked with 4.32" of rain in 24 hours. Woodside had 9.59" during the Columbus Day Storm, Skylonda 8.07" in 24 hours, and Belmont had 4.47" in 24 hours. Yreka saw 4.97" in six days. It seems that in the rain department, as with the peak gusts, December 1995 surpassed the Columbus Day Storm at some locations.

Location	Event	Time
Redway, CA (Humboldt Co.)	1 fatality from tree falling on house.	NA
Redding, CA (Shasta Co.)	1 fatality from tree falling on house.	NA
Sunnyvale, CA (Santa Clara Co.)	45 mph gust. Several trees down and numerous arcing power lines.	2:30 AM
Stanta Cruz Mts., CA (Santa Cruz Co.)	70 mph wind gust.	4:00 AM
Marin County, CA	70 mph wind gust.	4:36 AM
San Francisco, CA (San Francisco Co.)	85 mph wind gust at San Francisco State University.	6:30 AM
Oakland, CA (Alameda Co.)	75 mph wind gust.	7:15 AM
Los Gatos, CA (Santa Clara Co.)	6.7" 24-hour rainfall.	7:35 AM
Mount Umunhum, CA (Santa Clara Co.)	97 mph wind gust.	7:45 AM
San Francisco Bay Area, CA	California Highway Patrol reports 150 weather- related accidents between 6:30 AM and 7:45 AM.	8:00 AM
Angel Island, CA (San Francisco Bay)	103 mph wind gust.	8:03 AM
Monterey, CA (Monterey Co.)	1 fatality from tree falling on moving car.	8:15 AM
Healdsburg, CA (Sonoma Co.)	7.7" 24-hour rainfall.	8:45 AM
San Bruno Mt., San Francisco, CA	205 foot local radio station tower blown down in 90+ mph wind.	9:00 AM
Monterey, CA (Monterey Co.)	1 fatality from tree falling on moving car.	9:15 AM
San Francisco, CA, Park Presidio	Road closed at tunnel due to flooding.	9:46 AM
Oakland, CA (Alameda Co.)	2.66" 45-minute rainfall.	10:00 AM
Sebastopol, CA (Sonoma Co.)	8.98" storm total rainfall. Many downed trees and widespread power outages.	10:00 AM
Belmont, CA (San Mateo Co.)	62 mph wind gust. 4.5" storm total rainfall.	10:30 AM
San Francisco, CA (San Francisco Co.)	Large sinkhole affected 25 families.	10:50 AM
Healdsburg, CA (Sonoma Co.)	15.01" storm total rainfall at Russian River. Numerous power lines and trees down.	1:00 PM
Cambria, CA (San Luis Obispo Co.)	8.0" rainfall from 8:00 AM to 1:15 PM.	1:25 PM
San Francisco, CA, Conservatory	10 million dollars damage due to structural failure, broken windows and plants destroyed.	4:00 PM

This is what John Monteverdi, Meteorologist at San Francisco State University, wrote on December 15, 1995 as he introduced a new website dedicated to the December 12, 1995 windstorm: "In case some people had not heard, peak winds in the SF Bay Region included 103 mph on Angel Island (sea level), 85 mph at San Francisco State University (100 ft, 3/4 mile inland) and 139 mph in the Diablo Range east of San Francisco. Rainfall totals included 5.56 at SFSU, 7.54 at Santa Rosa and over 15 inches in Ross. Some evidence of possible wet microburst-related damage in southwestern SF. Most portions of southwestern SF look like a hurricane swept through (of course, you say, these were hurricane force winds)." [Italics mine.]

California Rainfall Table 12, below, a version of which appeared in the Oakland Tribune, shows the storm total rainfall of the December 1995 winstorm compared to the season total for 1995-96 (which begins on June 1st in California) as of December 12, 1995. The percentages are high, reflecting a very dry autumn up to the time of the big storm. Had the tempest struck at a time of more normal precipitation, then the flood damage from the heavy rainfall totals of Dec 12 would probably have been worse. Original source of the data: AccuWeather.

Location (All in the greater San Francisco Bay Area) Storm Total as of 5 PM Tuesday, December 12, 1995 Season Total Rainfall as of 5 PM Tuesday, December 12, 1995 % of Season Total that the Dec 12, 1995 Storm Represented Alameda 4.04" 4.45" 90.1% Fremont 2.66" 3.01" 88.3% Hayward 3.87" 4.20" 92.1% Livermore 2.60" 2.64" 98.5% Oakland 3.02" M --- Pleasanton 4.20" 4.28" 98.1% San Francisco 5.01" 6.00" 83.5% San Ramon 4.33" 4.74" 91.3% Dublin 4.00" 4.19" 95.4%

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